import unittest


class Demo01:
    pass


class Demo02:
    pass


class TestDemo(unittest.TestCase):
    def test01(self):
        d01 = Demo01()
        self.assertIsInstance(d01, Demo01, 'test msg.')

    def test02(self):
        d02 = Demo02()
        self.assertIsInstance(d02, Demo01, 'test msg')


if __name__ == '__main__':
    unittest.main()
